main(List<String> args) {
  //List 类型
  List<String> names = ["元素1", "元素2", "元素3", "元素2"];

//去重：遍历循环
  List<String> newNmaes = [];
  for (String name in names) {
    if (!newNmaes.contains(name)) {
      newNmaes.add(name);
    }
  }
  print(newNmaes);
  //去重：转Set类型
  List<String> newName2 = List.from(Set.from(names));
  print(newName2);

  //Set 类型 （不允许重复）
  Set<int> nums = {1, 2, 3, 4, 1};
  //print(nums);

  //Map 类型

  Map<String, dynamic> info = {
    "键1" : "值",
    "键2" : 0
  };
}
